Hand-rotated rock drill



May 25,1925. 1,585,821

L. c. BAYLES HAND ROTATED ROCK DRILL Filed Dec. 30, 1922 V lNVENTOR I 12mm; flfi les.

s-us AT'i'O NEY Patented May 25, 1926,

UNITED STATES LEWIS C. BAYLES, OF EASTON, PENNSYLVANIA, ASSIG-NOR T0 INGERSOLL-RAND COM- IPANY, 0F JERSEY QITY NEW JERSEY, A COREOBATION OF NEW JERSEY.

* HAND-ROTATED ROCK DRILL.

Application filed December 30, 1922: Serial No. 609,821.

and forth thereby rotating the drill steel through part of a revolution, as for instance, through an arc of about 180 to 200 de pending upon the operator himself and to some extent upon the conditions encountered. V

The object of the present invention is to enable the operator-to control or reduce the power of the air feeding element if the drill steel sticks, or when the resistance to rotation exceeds a predetermined amount, and to further permit the operator to so control the feeding element without taking his hand from the rotation handle.

Another object of the invention is to construct a relief valve for the air feeding element in such manner that it will be operated to reduce the feed pressure by movement of the rotation handle relatively to the rock drill. In order to accomplish this object, means are provided exerting a force on the relief valve opposed to the leverage pressure on the rotation handle, and this opposed force is sutiicient to prevent the relief valve from opening under normal pressure exerted by the rotation handle on the valve, but permitting the valve to open when the resistance to rotation exceeds a predetermined amount.

A still further object of the invention is to secure means for operating the relief valve when required by rocking the rotation handle about a pivot, in either direction, so that the operator may either push or pull on the handle with sufficient force, when the drill steel sticks, to overcome the force applied to the valve opposing the handle and thus opening the relief valve and reducing the air feed.

The invention is shown in one of its preferred forms in the accompanying drawings, in which Figure 1 is a side elevation partly in longitudinal section of a stope drill having the invention applied thereto, and

Figure 2 is a horizontal transverse sectional view on the line 22 of Figure 1 looking in the direction of the arrows.

Referring to the drawings, the rock drill comprises acasing including a percussive element, and meansfor feeding the machine forward in the form of a fluid actuated feeding element, The casing includes the drill cylinder A, the front head'B, the back cylinder extension C and the head block I) to which the air feed cylinder E is suitably connected by means of the side bolts, not shown. The air feed piston F is provided with the piston rod G, having the pointer H. The drill steel J extends into the front head B in position to be acted upon by the anvil block K, which receives the blows of impact of the reciprocating hammer piston L. Motive fluid is supplied to the machine through the inlet controlled by the throttle P'having theusual handle Q andthe motive fluid passes to the percussive element through: the passage R. The ports and passages for the operation of the piston are not indicated as they form no part of the present invention.

Motive fluid from the throttle P is led to to air feed cylinder E through the supply passage S, and a vent T from the air feed cylinder under the control of the relief valve U, is adapted to communicate with the passage V leading to atmosphere. The valve U is movable in the valve chamber V] and in this instance, is forced in one direction by the comparatively strong coiled spring X adapted to be compressed between the valve and the plug Y. The extension Z on the valve extends through the head block D and as shown bears against a tongue 0 pivoted at b on a boss 0 on the head block D. A rotation handle at is pivoted at e on the boss 0 and is provided with the fingers f and 9 adapted to bear on the tongue at. This handle d is adapted to be grasped by the operator for rotating the machine through part of a revolution, thus rotating the drill steel through part of a revolution. As long as the machine is free to rotate, that is, in case great resistance to rotation is not encountered and provided the drill steel does not stick, the comparatively stiff spring X will force the valve U outwardly and maintain it in the position indicated in the drawings, so that the handle d will be held substantially rigidly in one position on the machine, and will not move materially in relation to the drill casing. If the drill steel J sticks owing to increased resistance to rotation, either the push or the pull of the operators hand upon the handle cl will produce sufficient leverage pressure upon the pivoted tongue a to force the valve inwardly against the spring X until the vent 'l and atmospheric passage V are brought into communication so that the air feed cylinder will be relieved and the feed will be reduced. The operator may continue to at least partially rotate the machine and work the drill steel loose, in which case the stiff spring X will return the valve U to normal position and the full strength of the air feed will be restored.

I claim: i 1. A relief valve device for the feed cylinder of a rock drill comprising a percussive cylinder, a pressure fluid feed cylinder, a head block between the cylinders, a relief valve located in the head block having a body portion and an extension, a handle pivoted to the head block for rotating the drill in opposite directions, lingers on said handle for actuating the valve when the handle is rotated in opposite directions, a tongue interposed between the extension and the fingers and constantly in contact therewith and means for holding the valve normally closed and for holding the handle normally stationary with relation to the drill.

2. A relief valve device for the feed cylinder of a rock drill comprising a percussive cylinder, a pressure fluid feed cylinder, a head block between the cylinders, a Valve chamber located in the head block, a valve having an extension located in the valve chamber, a handle pivoted to the head block having lingers for actuating the valve when the handle is rotated in opposite directions. a tongue interposed between the end of said extension and the lingers of said handle, and means whereby manual pressure placed on the valve by means of the handle will cause it to actuate, relieving pressure in the feed cylinder.

3. A relief valve device for the feed cylinder of a rock drill comprising a percussive cylinder, a pressure fluid feed cylinder, :1 head block between the cylinders, a valve chamber located in the head block, a piston valve in the said valve chamber having an extension, a handle pivoted to the head block for rotating the drill in opposite directions,

specification.

LEWIS C. BAYLES. 

